1. Field of the Invention
The present invention relates to a power transmission apparatus for a vehicle that can implement smooth start and transmission by adding an electric supplementary drive unit and torque converting device to a double clutch transmission device, and improve fuel efficiency and acceleration performance.
2. Description of Related Art
Environment-friendly technology in a vehicle is core technology for survival of a future automobile industry and automakers devote all their energy to developing an environment-friendly automobile for getting over environmental and fuel efficiency regulations.
Examples of future automobile technologies may include an electric vehicle (EV) using electric energy, a hybrid electric vehicle (HEV), and a double clutch transmission (DCT) of which efficiency and convenience are improved.
Further, the automakers have made efforts to commercialize technologies such as an idle stop and go (ISG) device and a regenerative braking system as means for meeting an exhaust gas regulation of each nation and improving efficiency of a power transmission system for improving fuel efficiency performance.
The ISG device is technology that stops an engine when the vehicle stops and starts the engine when the vehicle starts, and the regenerative braking system is technology that drives a generator by using kinetic energy of the vehicle instead of existing braking by friction when the vehicle is braked and stores the resulting electric energy in a battery and reuses the stored electric energy when the vehicle is driven.
In addition, the hybrid electric vehicle which can adopt the transmission apparatus of the present invention as an automobile using two or more power sources may have various types of combinations, and in general, a hybrid of a gasoline engine or a diesel engine using existing fossil fuel and a motor/generator driven by the electric energy is provided.
As a transmission which can be adopted by the hybrid electric vehicle, the double clutch transmission (DCT) may be used as one example and the DCT applies two clutches to a manual transmission structure to increase efficiency and improve convenience.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.